This study is designed to profile the characteristics of EFSCH patients with histologically proven adenocarcinoma of the colon and rectum to (1) summarize observations and conclusions derived from all EFSCH colon studies, (2) compare current computer output with that reported in 1967 to ascertain whether more complete and longer term follow-up has altered the prognostic ranking of the variables, (3) code additional cases referred between 1961 and 1974, and (4) identify subsets of cases whose patterns of treatment failure might be beneficially changed by use of altered surgical techniques, preoperative or postoperative radiotherapy, chemotherapy or immunotherapy. A single code sheet will be developed incorporating all questions on previous code sheets and a computer program developed to print out new and previously abstracted data. Frequency distributions and life tables for each variable with standard deviations and age corrections will be done. Existing programs will be adapted to categorize cases that can be associated with identified patterns of behavior. This approach will provide greater specificity in case selection for clinical trials requisite to enhance the longevity of persons with cancers of the large intestine and rectum.